Value Assumptions in Risk Assessment is a case study of the Alachlor Controversy of 1985 in which the Canadian Minister of Agriculture cancelled the registration of the herbicide alachlor. This book demonstrates the opinion that risk assessments by scientific experts as well as ordinary citizens are guided by dominant values held by the assessors. It examines what these values typically are, how they work within a risk assessment, and some implications of reconsidering risk debates as primarily debates about values. Throughout, the book draws the conclusion that such debates are not primarily debates about science itself, but rather consist of political debate among different value frameworks, different ways of thinking about moral values, different conceptions of society, and different attitudes toward technology and toward risk-taking itself. The larger question in the analysis of these risk assessments is which set of values will ultimately prevail.